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From:Leonardo Francalanci Date:June 21 2004 4:57pm
Subject:why CPU is high while disks are idle in a table scan???
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I'm doing some tests on a 16.000.000 rows table.
Doing a simple "SELECT SUM(MYFIELD) FROM MYTABLE" I noticed
that disks are at 0.1%, while cpu arrives up to 80%.
How is that possible? My HDs are IDE. MySql has around
30Mb of ram, I thought it should read a lot from disk.

Even doing lots of queries by key I get only high cpu usage,
not disk reads.

Is that normal?
Thread
• why CPU is high while disks are idle in a table scan???Leonardo Francalanci21 Jun
  • Re: why CPU is high while disks are idle in a table scan???Jeremy Zawodny21 Jun
    • R: why CPU is high while disks are idle in a table scan???Leonardo Francalanci21 Jun
      • Re: R: why CPU is high while disks are idle in a table scan???Jeremy Zawodny21 Jun
        • R: R: why CPU is high while disks are idle in a table scan???Leonardo Francalanci21 Jun
          • Re: R: R: why CPU is high while disks are idle in a table scan???Jeremy Zawodny21 Jun
  • Re: why CPU is high while disks are idle in a table scan???Brent Baisley21 Jun
    • R: why CPU is high while disks are idle in a table scan???Leonardo Francalanci21 Jun
• Re: R: why CPU is high while disks are idle in a table scan???SGreen21 Jun
  • R: R: why CPU is high while disks are idle in a table scan???Leonardo Francalanci22 Jun
• Re: R: R: why CPU is high while disks are idle in a table scan???SGreen22 Jun
  • R: R: R: why CPU is high while disks are idle in a table scan???Leonardo Francalanci22 Jun